14 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Chester | 1 | 6,680 | 6,810 | -0.39% | 1,157 | 5.77 | City |
| Sparta | 2 | 3,986 | 4,081 | -0.47% | 357 | 11.16 | City |
| Red Bud | 3 | 3,720 | 3,794 | -0.4% | 1,418 | 2.62 | City |
| Steeleville | 4 | 1,871 | 1,918 | -0.48% | 1,228 | 1.52 | Village |
| Sparta township | 5 | 1,018 | 1,060 | -0.49% | 28 | 36.10 | Township |
| Percy | 6 | 906 | 913 | -0.11% | 924 | 0.98 | Village |
| Coulterville | 7 | 823 | 832 | -0.24% | 1,446 | 0.57 | Village |
| Tilden | 8 | 743 | 747 | -0.13% | 762 | 0.97 | Village |
| Chester township | 9 | 647 | 652 | 0% | 17 | 38.30 | Township |
| Evansville | 10 | 532 | 547 | -0.56% | 675 | 0.79 | Village |
| Ellis Grove | 11 | 324 | 326 | 0% | 660 | 0.49 | Village |
| Baldwin | 12 | 307 | 314 | -0.32% | 461 | 0.67 | Village |
| Rockwood | 13 | 31 | 33 | 0% | 146 | 0.21 | Village |
| Kaskaskia | 14 | 23 | 23 | 0% | 217 | 0.11 | Village |
Chester is the largest city in Randolph County, with a population of 6,680.
Kaskaskia is the smallest city in Randolph County.
There are 14 cities in Randolph County, Illinois.